The present invention is directed toward a piano-type key actuator, and more specifically, toward one that employs supplemental actuation, so as to enable an associated key to become engaged by applying a typical actuation force at any point along its length, including points within the immediate vicinity of its pivot point, thereby enabling the entire length of that key to be utilized for playing.
As musical instruments go, 88-key piano keyboards are somewhat difficult to lug around due to their size. In an attempt to improve their portability, manufacturers have offered keyboards with a reduced number of keys, as well as a reduced key size; however, such improvements tend to limit the functionality of the keyboard, which may, in turn, prevent it from being used for serious playing.
This invention addresses that keyboard portability issue by providing an actuator that enables a piano key to become engaged when a typical actuation force is applied anywhere along its entire length. Due to the prohibitively large actuation force that would generally be required to actuate a piano key near its pivot point, that end of the key is typically blocked by the casing of the keyboard. Since the present invention would enable a piano key to be actuated from any point along its length, the previously blocked key portion can be eliminated, and a more compact and portable keyboard can be provided, while still maintaining full keyboard functionality.
It should be understood that, although the present invention is described below with respect to actuators for piano-type keys, which includes keys for electronic and acoustic pianos, as well as for organs, accordions, and other keyboard instruments, this invention is in no way limited to such actuators, and could just as easily have been described with respect to actuators for any type of lever beam or actuated mechanism by one skilled in the art.
As such, a piano keyboard will be recognized by one skilled in the art as a lever actuator apparatus, where each piano key can be viewed as a lever, consisting of a lever beam connected to a fulcrum around which the lever beam can be displaced by an actuation force applied perpendicularly to its top surface, where the lever arm portion of the lever beam extends, from the location of the fulcrum along the lever beam, to the location of the applied actuation force along the lever beam, and where displacement of the lever arm pivotally actuates a linked mechanism to sound an associated note.
When a nominal actuation force is applied to the lever beam in very close proximity to the fulcrum, the resulting lever arm length will undoubtedly be insufficient to pivotally actuate the linked mechanism. To remedy this situation, the present invention provides a first supplemental actuation means that will instead linearly displace the lever arm in the direction of the applied force, so as to trigger the linked mechanism.
Similarly, if a nominal actuation force is applied in not-so-close proximity to the fulcrum, the resulting lever arm length may still be insufficient to pivotally actuate the linked mechanism. To remedy this situation, the present invention lines the lever beam with touch sensors along its top surface to quantify the resulting lever arm length, and it provides a second supplemental actuation means, that will augment the actuation force with an auxiliary force that is inversely proportional to the lever arm length, and that will pivotally displace the lever arm with the augmented actuation force, so as to trigger the linked mechanism.
It should also be understood that, while the present invention is described below with respect to a single, piano, white key, this is for illustrative purposes only, and should in no way be construed as a limitation on the application of the invention. In fact, piano keyboards have historically been associated with many types of key combinations and arrangements, from the standard interleaved pattern of 5 black and 7 white keys, to countless other non-standard patterns, and as would be obvious to one skilled in the art, the present invention is applicable to all such combinations and arrangements of keys.
It should further be understood that, although this invention is described below with respect to a simple key, hinge, and momentary, pushbutton switch, this is, again, for illustrative purposes, and again, should, in no way be construed as a limitation on the application of the invention. In fact, piano keyboards have long been associated with numerous expression enhancements, including countless types of sustain pedals, weighted-action keys, touch-sensitive keys, velocity-sensitive keys, pressure-sensitive keys, displacement-sensitive keys, etc., and as would be obvious to one skilled in the art, the present invention is applicable to all such expression enhancements.
As should be evident from the above discussion, the present invention is very broad in scope.